The invention is particularly well suited for use in connection with a railroad car bolster wherein the capacity of the dampening mechanism coacting between the sideframes and bolster is increased by enlarging the wedge shoes to increase the wedging surfaces and size of the springs which load the wedge shoes. The larger wedge shoes necessitate increasing the size of the wedge shoe pockets in the bolster by cutting more deeply into the bolster which weakens the bolster and creates higher stresses in the areas of the pockets, thereby making the bolster more susceptible to fatigue and fracturing in these vital areas. The invention is directed to substantially decreasing such stresses so that fatigue and fracturing of the bolster is less likely to occur when larger than normal wedge shoes are used.
Briefly stated, the invention is in an improved bolster having at each opposing end, a pair of pockets for receiving a pair of larger than normal, conventionally shaped wedge shoes used in dampening forces between the bolster and a pair of attached sideframes to which the wheels of the railroad car truck are mounted. The triangularly shaped pockets extend between the top and bottom walls of the bolster and are each located between a pair of projecting lugs that are designed to contain the sideframes on the bolster. A pair of coplanar sidewalls inboard and outboard are located between each pocket and an adjacent pair of lugs and intersect the top wall, the outboard sidewalls being closer the outer free ends of the bolster. The upper portions of the outboard sidewalls, adjacent to top wall of the bolster, are recessed inwardly of the bolster towards the longitudinal axis thereof, so that the sideframes as they rock in vertical planes, will not contact the upper portions of the outboard sidewalls, since contact of the sideframes with the upper portions of the outboard sidewalls produce a twisting action that unduly stresses the decreased sections of the bolster in the enlarged pockets and causes fracturing of the bolster in these areas. Thus, contact between the sideframes and bolster adjacent the top wall of the bolster, is shifted to the sturdier inboard sidewalls of the bolster.